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    <title>Document</title>
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        /* body {
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        .bgc .one {
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        .bgc .two {
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        .bgc .three {
        /* 背景透明 */
        /* background-color: transparent;
        } */ 
         body {
            background-color: wheat;
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         div {
            background-image: url(./zhong.jpg);
            width: 500px;
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        学习背景
    </div>
    <!-- <div class="bgc">
	  <div class="one">红色背景</div>
	  <div class="two">绿色背景</div>
	  <div class="three">透明背景</div>
    </div> -->
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